Efficacy of a food supplement in correcting riboflavin deficiency in pregnant Gambian women.

Pregnant women living in rural Gambian villages, whose natural riboflavin intake is about 0.5 mg/d, have abnormal biochemical riboflavin status and signs of clinical deficiency. A vitamin-fortified food supplement given in one village which increased the riboflavin intake to about 1.3 mg/d was followed by a substantial improvement in biochemical status, although seasonally-related variations in status somewhat complicated the picture. It was calculated that the amount of riboflavin needed to satisfy the requirement, for normal biochemical status, of the majority of pregnant women throughout pregnancy and throughout the year, is about 2.6 mg/d. Clinical signs associated with riboflavin deficiency, especially atrophic lingual papillae, showed significantly reduced incidence in the supplemented, compared with an unsupplemented, village. Cord blood values of the activation coefficient of erythrocyte glutathione reductase were in the abnormal range for 84 per cent of infants before introduction of the supplement, but were abnormal for only one of 12 infants after its introduction. Thus even a suboptimal maternal riboflavin intake of about 1.3 mg/d appears to be sufficient to prevent biochemical deficiency in cord blood, and to reduce considerably the incidence of clinical deficiency signs during pregnancy.